I recently bought here on the forum a really nice X61s w/ SXGA+ xiphmont LED lcd. It behaves pretty well with its stock L7500 mobo - but I want a bit more It has some driver problems, but this is nothing new that our beloved Lenovo throws rocks at us oldschoolers...

I came by a very cheap (the likes of $30) motherboards of X61s and X61, with L7700, T8300 and T9300 respectively. Having in mind just the rough power of the unit, T9300 would be the best choice with double the cache that T8300 has. As for the heat output and power consumption... Well, this is the place I'd like to ask you for your possible choice.

I have chosen a T8300 CPU motherboard. It is way more powerful than both L7500 and L7700, while being just a little less powerful than T9300. Being hotter than L-series (35W TDP to 17W TDP) makes me wonder, but on the other side it's a bit thicker X61 chassis that should handle the extra heat better. Not to mention that I will possibly use throttlestop to seriously undervolt the CPU.

wujstefan wrote:
I have chosen a T8300 CPU motherboard. It is way more powerful than both L7500 and L7700, while being just a little less powerful than T9300. Being hotter than L-series (35W TDP to 17W TDP) makes me wonder, but on the other side it's a bit thicker X61 chassis that should handle the extra heat better. Not to mention that I will possibly use throttlestop to seriously undervolt the CPU.

Will have to find out. What are your thoughts?

I recently acquired a T8300 X61. I've been investigating how well it dissipates heat, however, I need to repaste the CPU and drill out the stripped screws of the WLAN and WWAN cards. I will report back in the next couple of days. Here's my thread on the topic:

I should have been more specific: the T7500 is the fastest among the Merom-based Core 2 Duos; models with T8xxx CPUs were introduced later (early 2008 IIRC).
I've yet to encounter an X61 T8300, so I don't know if it has the rightmost heatsink or not.

axur-delmeria wrote:I should have been more specific: the T7500 is the fastest among the Merom-based Core 2 Duos; models with T8xxx CPUs were introduced later (early 2008 IIRC).
I've yet to encounter an X61 T8300, so I don't know if it has the rightmost heatsink or not.

Back to topic, the 2nd heatsink is what's needed for an X61/s conversion. The fan connector needs to be modified as well, as X61s fans have a 4-pin connector (but only 3 wires) while the normal X61 has a 3-pin connector.

Undervolting is a necessity, and you might end up limiting the max CPU clock to 2.0 or 2.2GHz as well.

Search for the heatsink tests by xiphmont, they methodically measured temperatures at 100% cpu usage on the x61.

I use the x61 base on my frankenpads.

There's hardly any difference between T9300 and T8300

The single thread performance is even more trival...but not for all applications. I'd guess, though I've never used the program, the larger L2 cache would be noticable in a cpu-intensive program like AutoCad.